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Deadly storms, including reported tornadoes, pounded Arkansas
yesterday (April 25), adding to what is likely to be a record
tornado count for the month of April.

Four deaths in Arkansas were reported from the severe storms
yesterday. If those deaths are attributed to tornadoes, the first
four months of 2011 will have matched the tornado death toll for
all of last year. These intense storms are not letting up today;
they're reloading and sweeping across the Midwest and Southeast.
[ In
Images: The Tornado Damage Scale ]

The Weather Channel has reported the confirmation of 292
tornadoes in the United States so far this month, besting the
previous April record of 267 in 1974. Storm survey teams continue
to assess the damage from this month's storms and could change
the number of confirmed tornadoes. The average for April is only
116, according to the SPC.

Remember '74

Counts of tornadoes and tornado damage today are higher than ever
due to more people reporting tornadoes, and more buildings being
hit as the country's population grows and its cities and towns
expand. Storm
chaser videos of funnel clouds are posted daily to YouTube,
and rarely does a small tornado go unnoticed anymore.

Carbin said that if April 1974 were adjusted to account for
unreported tornadoes, an extra hundred or so could be added to
its total.

Along with amazing videos of twin and even
triplet tornadoes have come new tornado records in several
states.

In North Carolina, 28 tornadoes have been confirmed for April 16,
a record outbreak for any single day there.

In Wisconsin, 14 tornadoes struck on April 10, the biggest
outbreak for any April day in the state's history.

Yet none of these outbreaks comes close to matching the
"granddaddy of them all," as Carbin called it — the "Super
Outbreak" of April 3-4, 1974, when more than 148 tornadoes were
confirmed and 330 people were killed.

Deadly spring

Tornadoes have killed 41 people this year, most of them in mobile
homes. The Arkansas deaths could push the total to 45, matching
the death toll for all of last year.

North Carolina has suffered the most this year, with 26 deaths,
all from a single April outbreak. That was the deadliest outbreak
in the state since the "Super Tuesday" storms of February 2008,
when 57 people died in
Dixie Alley, the southeastern extension of Tornado Alley.

In 2008, during a season among the all-time highest for number of
tornadoes, 126 people were killed. As staggering as these death
tolls are, they've been dramatically reduced in recent years due
to
better forecasting and warnings.

Mike Smith, chief executive officer of Weather Data Services, a
part of AccuWeather, believes that at least 100 lives were saved
by the warnings before a massive EF-4 tornado — the
strongest of the year so far — struck near St. Louis on Good
Friday (April 22).

This spring's severe weather seems to be rapidly reloading
between storms. That could be due to a lingering La Niña — the
opposite phase of El Niño — when the equatorial waters of the
Pacific Ocean are abnormally cool, said Grady Dixon, a
climatologist and meteorologist at Mississippi State University
in Starkville.

Along with creating dry weather in the Southwest, contributing to
the
historic wildfires in Texas, La Niña tends to guide the jet
stream north through the Pacific Northwest and Great Lakes,
trapping cold air on the northern side and the warm, humid air
needed for thunderstorms on the southern side.

"This setup means that the southern U.S. experiences ample
moisture without many cold fronts sweeping through to dry out the
atmosphere." Dixon said. "This allows rapid recharge in between
severe events."

Not all La Niña events are associated with highly active severe
weather seasons, Dixon said, but some years with similar La Niña
characteristics are also historic tornado years, including 1974,
1999 ― which saw an EF-5 tornado devastate Moore, Okla. ― and
2008.